Oral therapeutic vaccination with Streptococcus sobrinus recombinant enolase confers protection against dental caries in rats.
Dental caries is among the more prevalent chronic human infections for which an effective human vaccine has not yet been achieved. Enolase from Streptococcus sobrinus has been identified as an immunomodulatory protein. In the present study, we used S. sobrinus recombinant enolase (rEnolase) as a target antigen and assessed its therapeutic effect in a rat model of dental caries. Wistar rats that were fed a cariogenic solid diet on day 18 after birth were orally infected with S. sobrinus on day 19 after birth and for 5 consecutive days thereafter. Five days after infection and, again, 3 weeks later, rEnolase plus alum adjuvant was delivered into the oral cavity of the rats. A sham-immunized group of rats was contemporarily treated with adjuvant alone. In the rEnolase-immunized rats, increased levels of salivary IgA and IgG antibodies specific for this recombinant protein were detected. A significant decrease in sulcal, proximal enamel, and dentin caries scores was observed in these animals, compared with sham-immunized control animals. No detectable histopathologic alterations were observed in all immunized animals. Furthermore, the antibodies produced against bacterial enolase did not react with human enolase. Overall, these results indicate that rEnolase could be a promising and safe candidate for testing in trials of vaccines against dental caries in humans.
Dinis
Márcia
M
Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Porto, Portugal.
Tavares
Delfina
D
Veiga-Malta
Isabel
I
Fonseca
António J M M
AJ
Andrade
Elva Bonifácio
EB
Trigo
Gabriela
G
Ribeiro
Adília
A
Videira
Arnaldo
A
Cabrita
António M Silvério
AM
Ferreira
Paula
P
D000284:Administration, Oral; D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000627:therapeutic use*; D003731:Dental Caries / Q000382:microbiology / Q000517:prevention & control*; D005260:Female; D007115:Immunization Schedule; D008297:Male; D009055:Mouth / Q000382:microbiology; D010751:Phosphopyruvate Hydratase / Q000627:therapeutic use*; D051381:Rats; D013290:Streptococcal Infections / Q000517:prevention & control*; D016986:Streptococcus sobrinus / Q000201:enzymology / Q000276:immunology* / Q000302:isolation & purification; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use*
D001428:Bacterial Vaccines; D014614:Vaccines, Synthetic; D010751:Phosphopyruvate Hydratase